Magnetoresistance effect element and magnetic memory

Abstract

Provided is a magnetoresistance effect element in which the magnetization direction of the recording layer is perpendicular to the film surface and which has a high thermal stability factor Δ, and a magnetic memory.A recording layer having a configuration of first magnetic layer/first non-magnetic coupling layer/first magnetic insertion layer/second non-magnetic coupling layer/second magnetic layer is sandwiched between the first and second non-magnetic layers and stacked so that a magnetic coupling force is generated between the first magnetic layer and the second magnetic layer.

The invention claimed is: 
     
       1. A magnetoresistance effect element comprising:
 a first non-magnetic layer; 
 a first magnetic layer provided adjacent to the first non-magnetic layer and having a magnetization direction which is perpendicular to a film surface; 
 a first non-magnetic coupling layer provided adjacent to the first magnetic layer on a side of the first magnetic layer opposite to the first non-magnetic layer; 
 a first magnetic insertion layer provided adjacent to the first non-magnetic coupling layer on a side of the first non-magnetic coupling layer opposite to the first magnetic layer; 
 a second non-magnetic coupling layer provided adjacent to the first magnetic insertion layer on a side of the first magnetic insertion layer opposite to the first non-magnetic coupling layer; 
 a second magnetic layer provided adjacent to the second non-magnetic coupling layer on a side of the second non-magnetic coupling layer opposite to the first magnetic insertion layer and having a magnetization direction which is perpendicular to the film surface; and 
 a second non-magnetic layer provided adjacent to the second magnetic layer on a side of the second magnetic layer opposite to the second non-magnetic coupling layer, wherein 
 the first non-magnetic layer and the second non-magnetic layer are constituted of a layer including O (oxygen); 
 the first magnetic layer and the second magnetic layer include at least either Co or Fe; 
 the first non-magnetic coupling layer and the second non-magnetic coupling layer include a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, V, B; 
 the first non-magnetic coupling layer and the second non-magnetic coupling layer has a film thickness of 0.2 nm or more and 1.3 nm or less; 
 the first magnetic insertion layer includes at least Fe and B; 
 the first magnetic insertion layer has a film thickness of 0.4 nm or more and 1.0 nm or less; 
 the first magnetic layer and the second magnetic layer are magnetically coupled by a first coupling layer constituted of the first non-magnetic coupling layer, the first magnetic insertion layer and the second non-magnetic coupling layer; and 
 the first magnetic layer, the first coupling layer, and the second magnetic layer constitute a first recording layer. 
 
     
     
       2. The magnetoresistance effect element according to  claim 1 , wherein
 the first coupling layer further comprises 
 a second magnetic insertion layer provided adjacent to the second non-magnetic coupling layer on the side of the second non-magnetic coupling layer opposite to the first magnetic insertion layer, and 
 a third non-magnetic coupling layer provided adjacent to the second magnetic insertion layer on a side of the second magnetic insertion layer opposite to the second non-magnetic coupling layer, and adjacent to the second magnetic layer on a side of the second magnetic layer opposite to the second non-magnetic layer wherein 
 the first non-magnetic coupling layer, the second non-magnetic coupling layer, and the third non-magnetic coupling layer include a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, V, B; 
 the first magnetic insertion layer and the second magnetic insertion layer include at least Fe and B; and 
 the first magnetic layer and the second magnetic layer are magnetically coupled by the first coupling layer constituted of the first non-magnetic coupling layer, the first magnetic insertion layer, the second non-magnetic coupling layer, the second magnetic insertion layer, and the third non-magnetic coupling layer. 
 
     
     
       3. The magnetoresistance effect element according to  claim 1 , wherein the first magnetic insertion layer further includes a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt. 
     
     
       4. The magnetoresistance effect element according to  claim 2 , wherein the first magnetic insertion layer or the second magnetic insertion layer further includes a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt. 
     
     
       5. The magnetoresistance effect element according to  claim 1 , wherein a magnetic coupling force J ex  per unit area between the first magnetic layer and the second magnetic layer is 0.1 mJ/m 2  or more. 
     
     
       6. The magnetoresistance effect element according to  claim 1 , comprising a saturation magnetization M s  of 0.4 T or more at a time of stacking the first magnetic insertion layer adjacent to the first non-magnetic coupling layer. 
     
     
       7. The magnetoresistance effect element according to  claim 2 , comprising a saturation magnetization M s  of 0.4 T or more at a time of stacking the first magnetic insertion layer adjacent to the first non-magnetic coupling layer and at a time of stacking the second magnetic insertion layer adjacent to the second non-magnetic coupling layer. 
     
     
       8. The magnetoresistance effect element according to  claim 1 , wherein
 the first magnetic layer is constituted of a first magnetic outer layer adjacent to the first non-magnetic layer, and a first magnetic inner layer provided adjacent to the first magnetic outer layer on a side of the first magnetic outer layer opposite to the first non-magnetic layer; and 
 a ratio of a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the first magnetic outer layer to a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the first magnetic inner layer is less than 1. 
 
     
     
       9. The magnetoresistance effect element according to  claim 1 , wherein
 the second magnetic layer is constituted of a second magnetic outer layer adjacent to the second non-magnetic layer, and a second magnetic inner layer provided adjacent to the second magnetic outer layer on a side of the second magnetic outer layer opposite to the second non-magnetic layer; and 
 a ratio of a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the second magnetic outer layer to a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the second magnetic inner layer is less than 1. 
 
     
     
       10. The magnetoresistance effect element according to  claim 1 , wherein
 the first coupling layer further comprises 
 a second magnetic insertion layer provided adjacent to the second non-magnetic coupling layer on the side of the second non-magnetic coupling layer opposite to the first magnetic insertion layer; 
 a third non-magnetic coupling layer provided adjacent to the second magnetic insertion layer on a side of the second magnetic insertion layer opposite to the second non-magnetic coupling layer; 
 a third magnetic insertion layer provided adjacent to the third non-magnetic coupling layer on a side of the third non-magnetic coupling layer opposite to the second magnetic insertion layer; and 
 a fourth non-magnetic coupling layer provided adjacent to and between the third magnetic insertion layer and the second magnetic layer, wherein 
 the first non-magnetic coupling layer, the second non-magnetic coupling layer, the third non-magnetic coupling layer, and the fourth non-magnetic coupling layer include a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, V, B; 
 the first magnetic insertion layer, the second magnetic insertion layer, and the third magnetic insertion layer include at least Fe and B; and 
 the first magnetic layer and the second magnetic layer are magnetically coupled by the first coupling layer constituted of the first non-magnetic coupling layer, the first magnetic insertion layer, the second non-magnetic coupling layer, the second magnetic insertion layer, the third non-magnetic coupling layer, the third magnetic insertion layer and the fourth non-magnetic coupling layer. 
 
     
     
       11. A magnetoresistance effect element comprising:
 a first non-magnetic layer; 
 a first magnetic layer provided adjacent to the first non-magnetic layer and having a magnetization direction which is perpendicular to a film surface; 
 a first non-magnetic coupling layer provided adjacent to the first magnetic layer on a side of the first magnetic layer opposite to the first non-magnetic layer; 
 a first magnetic insertion layer provided adjacent to the first non-magnetic coupling layer on a side of the first non-magnetic coupling layer opposite to the first magnetic layer; 
 a second non-magnetic coupling layer provided adjacent to the first magnetic insertion layer on a side of the first magnetic insertion layer opposite to the first non-magnetic coupling layer; 
 a second magnetic layer provided adjacent to the second non-magnetic coupling layer on a side of the second non-magnetic coupling layer opposite to the first magnetic insertion layer and having a magnetization direction which is perpendicular to the film surface; 
 a third non-magnetic layer provided adjacent to the second magnetic layer on a side of the second magnetic layer opposite to the second non-magnetic coupling layer; 
 a third magnetic layer provided adjacent to the third non-magnetic layer on a side of the third non-magnetic layer opposite to the second magnetic layer and having a magnetization direction which is perpendicular to the film surface; 
 a fifth non-magnetic coupling layer provided adjacent to the third magnetic layer on a side of the third magnetic layer opposite to the third non-magnetic layer; 
 a fourth magnetic insertion layer provided adjacent to the fifth non-magnetic coupling layer on a side of the fifth non-magnetic coupling layer opposite to the third magnetic layer; 
 a sixth non-magnetic coupling layer provided adjacent to the fourth magnetic insertion layer on a side of the fourth magnetic insertion layer opposite to the fifth non-magnetic coupling layer; 
 a fourth magnetic layer provided adjacent to the sixth non-magnetic coupling layer on a side of the sixth non-magnetic coupling layer opposite to the fourth magnetic insertion layer and having a magnetization direction which is perpendicular to the film surface; and 
 a second non-magnetic layer provided adjacent to the fourth magnetic layer on a side of the fourth magnetic layer opposite to the sixth non-magnetic coupling layer, wherein 
 the first non-magnetic layer and the second non-magnetic layer are constituted of a layer including O (oxygen); 
 the first magnetic layer, the second magnetic layer, the third magnetic layer, and the fourth magnetic layer include at least either Co or Fe; 
 the first non-magnetic coupling layer, the second non-magnetic coupling layer, the fifth non-magnetic coupling layer, and the sixth non-magnetic coupling layer include a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, V, B; 
 the first non-magnetic coupling layer and the second non-magnetic coupling layer has a film thickness of 0.2 nm or more and 1.3 nm or less; 
 the first magnetic insertion layer and the fourth magnetic insertion layer include at least Fe and B; 
 the first magnetic insertion layer has a film thickness of 0.4 nm or more and 1.0 nm or less; 
 the third non-magnetic layer includes an oxide of a non-magnetic element; 
 the first magnetic layer and the second magnetic layer are magnetically coupled by a first coupling layer constituted of the first non-magnetic coupling layer, the first magnetic insertion layer and the second non-magnetic coupling layer; 
 the second magnetic layer and the third magnetic layer are magnetically coupled by a second coupling layer constituted of the third non-magnetic layer; 
 the third magnetic layer and the fourth magnetic layer are magnetically coupled by a third coupling layer constituted of the fifth non-magnetic coupling layer, the fourth magnetic insertion layer and the sixth non-magnetic coupling layer; 
 the first magnetic layer and the fourth magnetic layer are magnetically coupled by the first coupling layer, the second coupling layer, and the third coupling layer; 
 the first magnetic layer, the first coupling layer, the second magnetic layer, the second coupling layer, the third magnetic layer, the third coupling layer, and the fourth magnetic layer constitute a first recording layer. 
 
     
     
       12. The magnetoresistance effect element according to  claim 11 , wherein the first magnetic insertion layer or the fourth magnetic insertion layer further includes a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt. 
     
     
       13. The magnetoresistance effect element according to  claim 11 , wherein a sum of a film thickness of the first magnetic insertion layer and a film thickness of the fourth magnetic insertion layer is greater than 0.4 nm and 1.6 nm or less. 
     
     
       14. The magnetoresistance effect element according to  claim 11 , wherein a magnetic coupling force J ex  per unit area between the first magnetic layer and the second magnetic layer is 0.1 mJ/m 2  or more, a magnetic coupling force J ex  per unit area between the second magnetic layer and the third magnetic layer is 0.1 mJ/m 2  or more, and a magnetic coupling force J ex  per unit area between the third magnetic layer and the fourth magnetic layer is 0.1 mJ/m 2  or more. 
     
     
       15. The magnetoresistance effect element according to  claim 11 , wherein
 the first magnetic layer is constituted of a first magnetic outer layer adjacent to the first non-magnetic layer, and a first magnetic inner layer adjacent to and sandwiched between the first magnetic outer layer and the first non-magnetic coupling layer; and 
 a ratio of a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the first magnetic outer layer to a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the first magnetic inner layer is less than 1. 
 
     
     
       16. The magnetoresistance effect element according to  claim 11 , wherein
 the second magnetic layer includes a second magnetic outer layer adjacent to the third non-magnetic layer, and a second magnetic inner layer adjacent to and sandwiched between the second magnetic outer layer and the second non-magnetic coupling layer; and 
 a ratio of a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the second magnetic outer layer to a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the second magnetic inner layer is less than 1. 
 
     
     
       17. The magnetoresistance effect element according to  claim 11 , wherein
 the third magnetic layer includes a third magnetic outer layer adjacent to the third non-magnetic layer, and a third magnetic inner layer adjacent to and sandwiched between the third magnetic outer layer and the fifth non-magnetic coupling layer; and 
 a ratio of a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the third magnetic outer layer to a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the third magnetic inner layer is less than 1. 
 
     
     
       18. The magnetoresistance effect element according to  claim 11 , wherein
 the fourth magnetic layer includes a fourth magnetic outer layer adjacent to the second non-magnetic layer, and a fourth magnetic inner layer adjacent to and sandwiched between the fourth magnetic outer layer and the sixth non-magnetic coupling layer; and 
 a ratio of a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the fourth magnetic outer layer to a composition of a non-magnetic element consisting of at least one of W, Ta, Hf, Zr, Nb, Mo, Ti, V, Cr, Si, Al, B, Pd, Pt, of the fourth magnetic inner layer is less than 1. 
 
     
     
       19. A magnetic memory including the magnetoresistance effect element according to  claim 1  as a magnetic memory cell. 
     
     
       20. The magnetoresistance effect element according to  claim 1 , wherein the first magnetic layer and the second magnetic layer include at least Fe and B. 
     
     
       21. The magnetoresistance effect element according to  claim 1 , wherein the first magnetic insertion layer comprises FeB.